The following disclosure relates generally to the field of orthoses and, more specifically, to an articulated ankle-foot orthosis controlled by the foot stance of the wearer.
Idiopathic toe walkers describes persons who walk without making heel contact during the initial contact phase of the gait cycle, yet have no signs of neurological, orthopaedic, or psychiatric diseases.
The existing conventional orthosis that is commonly prescribed for idiopathic toe walkers improves heel contact by restricting plantar flexion of the foot (downward rotation of the foot, relative to the ankle). Restricted plantar flexion, however, causes other problems and impedes the development of a normal walking gait. Without plantar flexion during the loading response period of the gait cycle, individuals have a smaller base of support, which limits the stability of their gait. Furthermore, without plantar flexion during the push-off period of the gait cycle, individuals cannot generate sufficient propulsion to advance the body efficiently. These limitations contribute to reports by wearers that the conventional ankle-foot orthosis is uncomfortable, significantly impairs walking, and produces dissatisfactory results. Motorized ankle-foot orthoses offer increased motion control, but are too complicated, expensive, bulky, and heavy for widespread use.
Accordingly, there is a need for improved ankle-foot orthoses that encourage a normal gait while providing stability, efficient propulsion, comfort, and improved clinical results.